package com.example.My.tools;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.parser.ParserConfig;
import com.alibaba.fastjson.serializer.SerializerFeature;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.type.TypeFactory;
import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.data.redis.serializer.SerializationException;

import java.nio.charset.Charset;

/**
 * Author: 谢宇
 * CreatTime 2023/11/5 11:33
 * Version 1.0.0
 *
 * 实现Redis使用FastJSON序列化
 */

public class RedisJson<T> implements RedisSerializer<T> {

    public static final Charset DEFAULT_CHARSET = Charset.forName("UTF-8");

    private Class<T> clazz;

    static {
        ParserConfig.getGlobalInstance().setAutoTypeSupport(true);
    }

    public RedisJson(Class<T> clazz) {
        super();
        this.clazz = clazz;
    }


    //序列化
    @Override
    public byte[] serialize(T t) throws SerializationException {
        //   当t为空时
        if(t == null){
            return new byte[0];
        }
        //返回获取的泛型toString之后的字节流
        return JSON.toJSONString(t, SerializerFeature.WriteClassName).getBytes(DEFAULT_CHARSET);
    }

    // 反序列化
    @Override
    public T deserialize(byte[] bytes) throws SerializationException {
        if(bytes == null || (bytes.length < 0 && bytes.length == 0)){
            return  null;
        }
        String str=new String(bytes,DEFAULT_CHARSET);
        return JSON.parseObject(str,clazz);
    }

    //
    protected JavaType getJavaType(Class<?> clazz) {
        return TypeFactory.defaultInstance().constructType(clazz);
    }
}
